/**
 * @author       Richard Davey <rich@photonstorm.com>
 * @copyright    2020 Photon Storm Ltd.
 * @license      {@link https://opensource.org/licenses/MIT|MIT License}
 */

 var Class = require('../../utils/Class');
 var FileTypesManager = require('../FileTypesManager');
 var ImageFile = require('./ImageFile.js');
 
 /**
  * @classdesc
  * A single Sprite Sheet Image File suitable for loading by the Loader.
  *
  * These are created when you use the Phaser.Loader.LoaderPlugin#spritesheet method and are not typically created directly.
  *
  * For documentation about what all the arguments and configuration options mean please see Phaser.Loader.LoaderPlugin#spritesheet.
  *
  * @class SpriteSheetFile
  * @extends Phaser.Loader.File
  * @memberof Phaser.Loader.FileTypes
  * @constructor
  * @since 3.0.0
  *
  * @param {Phaser.Loader.LoaderPlugin} loader - A reference to the Loader that is responsible for this file.
  * @param {(string|Phaser.Types.Loader.FileTypes.SpriteSheetFileConfig)} key - The key to use for this file, or a file configuration object.
  * @param {string|string[]} [url] - The absolute or relative URL to load this file from. If undefined or `null` it will be set to `<key>.png`, i.e. if `key` was "alien" then the URL will be "alien.png".
  * @param {Phaser.Types.Loader.FileTypes.ImageFrameConfig} [frameConfig] - The frame configuration object.
  * @param {Phaser.Types.Loader.XHRSettingsObject} [xhrSettings] - Extra XHR Settings specifically for this file.
  */
 var SpriteSheetFile = new Class({
 
     Extends: ImageFile,
 
     initialize:
 
     function SpriteSheetFile (loader, key, url, frameConfig, xhrSettings)
     {
         ImageFile.call(this, loader, key, url, xhrSettings, frameConfig);
 
         this.type = 'spritesheet';
     },
 
     /**
      * Adds this file to its target cache upon successful loading and processing.
      *
      * @method Phaser.Loader.FileTypes.SpriteSheetFile#addToCache
      * @since 3.7.0
      */
     addToCache: function ()
     {
         this.cache.addSpriteSheet(this.key, this.data, this.config);
     }
 
 });
 
 /**
  * Adds a Sprite Sheet Image, or array of Sprite Sheet Images, to the current load queue.
  *
  * The term 'Sprite Sheet' in Phaser means a fixed-size sheet. Where every frame in the sheet is the exact same size,
  * and you reference those frames using numbers, not frame names. This is not the same thing as a Texture Atlas, where
  * the frames are packed in a way where they take up the least amount of space, and are referenced by their names,
  * not numbers. Some articles and software use the term 'Sprite Sheet' to mean Texture Atlas, so please be aware of
  * what sort of file you're actually trying to load.
  *
  * You can call this method from within your Scene's `preload`, along with any other files you wish to load:
  *
  * ```javascript
  * function preload ()
  * {
  *     this.load.spritesheet('bot', 'images/robot.png', { frameWidth: 32, frameHeight: 38 });
  * }
  * ```
  *
  * The file is **not** loaded right away. It is added to a queue ready to be loaded either when the loader starts,
  * or if it's already running, when the next free load slot becomes available. This happens automatically if you
  * are calling this from within the Scene's `preload` method, or a related callback. Because the file is queued
  * it means you cannot use the file immediately after calling this method, but must wait for the file to complete.
  * The typical flow for a Phaser Scene is that you load assets in the Scene's `preload` method and then when the
  * Scene's `create` method is called you are guaranteed that all of those assets are ready for use and have been
  * loaded.
  *
  * Phaser can load all common image types: png, jpg, gif and any other format the browser can natively handle.
  * If you try to load an animated gif only the first frame will be rendered. Browsers do not natively support playback
  * of animated gifs to Canvas elements.
  *
  * The key must be a unique String. It is used to add the file to the global Texture Manager upon a successful load.
  * The key should be unique both in terms of files being loaded and files already present in the Texture Manager.
  * Loading a file using a key that is already taken will result in a warning. If you wish to replace an existing file
  * then remove it from the Texture Manager first, before loading a new one.
  *
  * Instead of passing arguments you can pass a configuration object, such as:
  *
  * ```javascript
  * this.load.spritesheet({
  *     key: 'bot',
  *     url: 'images/robot.png',
  *     frameConfig: {
  *         frameWidth: 32,
  *         frameHeight: 38,
  *         startFrame: 0,
  *         endFrame: 8
  *     }
  * });
  * ```
  *
  * See the documentation for `Phaser.Types.Loader.FileTypes.SpriteSheetFileConfig` for more details.
  *
  * Once the file has finished loading you can use it as a texture for a Game Object by referencing its key:
  *
  * ```javascript
  * this.load.spritesheet('bot', 'images/robot.png', { frameWidth: 32, frameHeight: 38 });
  * // and later in your game ...
  * this.add.image(x, y, 'bot', 0);
  * ```
  *
  * If you have specified a prefix in the loader, via `Loader.setPrefix` then this value will be prepended to this files
  * key. For example, if the prefix was `PLAYER.` and the key was `Running` the final key will be `PLAYER.Running` and
  * this is what you would use to retrieve the image from the Texture Manager.
  *
  * The URL can be relative or absolute. If the URL is relative the `Loader.baseURL` and `Loader.path` values will be prepended to it.
  *
  * If the URL isn't specified the Loader will take the key and create a filename from that. For example if the key is "alien"
  * and no URL is given then the Loader will set the URL to be "alien.png". It will always add `.png` as the extension, although
  * this can be overridden if using an object instead of method arguments. If you do not desire this action then provide a URL.
  *
  * Phaser also supports the automatic loading of associated normal maps. If you have a normal map to go with this image,
  * then you can specify it by providing an array as the `url` where the second element is the normal map:
  *
  * ```javascript
  * this.load.spritesheet('logo', [ 'images/AtariLogo.png', 'images/AtariLogo-n.png' ], { frameWidth: 256, frameHeight: 80 });
  * ```
  *
  * Or, if you are using a config object use the `normalMap` property:
  *
  * ```javascript
  * this.load.spritesheet({
  *     key: 'logo',
  *     url: 'images/AtariLogo.png',
  *     normalMap: 'images/AtariLogo-n.png',
  *     frameConfig: {
  *         frameWidth: 256,
  *         frameHeight: 80
  *     }
  * });
  * ```
  *
  * The normal map file is subject to the same conditions as the image file with regard to the path, baseURL, CORs and XHR Settings.
  * Normal maps are a WebGL only feature.
  *
  * Note: The ability to load this type of file will only be available if the Sprite Sheet File type has been built into Phaser.
  * It is available in the default build but can be excluded from custom builds.
  *
  * @method Phaser.Loader.LoaderPlugin#spritesheet
  * @fires Phaser.Loader.LoaderPlugin#ADD
  * @since 3.0.0
  *
  * @param {(string|Phaser.Types.Loader.FileTypes.SpriteSheetFileConfig|Phaser.Types.Loader.FileTypes.SpriteSheetFileConfig[])} key - The key to use for this file, or a file configuration object, or array of them.
  * @param {string} [url] - The absolute or relative URL to load this file from. If undefined or `null` it will be set to `<key>.png`, i.e. if `key` was "alien" then the URL will be "alien.png".
  * @param {boolean} [isStatic=false] - 是否是静态资源 
  * @param {Phaser.Types.Loader.FileTypes.ImageFrameConfig} [frameConfig] - The frame configuration object. At a minimum it should have a `frameWidth` property.
  * @param {Phaser.Types.Loader.XHRSettingsObject} [xhrSettings] - An XHR Settings configuration object. Used in replacement of the Loaders default XHR Settings.
  *
  * @return {this} The Loader instance.
  */
 FileTypesManager.register('spritesheet', function (key, url, isStatic, frameConfig, xhrSettings)
 {
     if (Array.isArray(key))
     {
         for (var i = 0; i < key.length; i++)
         {
             //  If it's an array it has to be an array of Objects, so we get everything out of the 'key' object
             this.addFile(new SpriteSheetFile(this, key[i]));
         }
     }
     else
     {
         this.addFile(new SpriteSheetFile(this, key, url, frameConfig, xhrSettings));
     }
 
     return this;
 });
 
 module.exports = SpriteSheetFile;
 